Brake Bleeding with ABS

[Hokiefyd]

I need to bleed the brakes on my '07 T&C. The fluid is dark, and even the dealer mentioned it on a recent warranty visit. Dealer's price for the bleed is $135.

The van has ABS. The procedure in the service manual talks about using the Chrysler scan tool to cycle the ABS pump and get the fluid in that out as well. Is cycling this ABS pump with the scan tool an absolute necessity? If it is, even a local garage would be incapable of doing the job I'd think. If it's not, I should be able to do it at home in my garage. I appreciate the suggestions in the other recent thread, about using a brick below the brake pedal to prevent excessive travel.

So I think I'm ready to do the job...if I can even do it myself. Any ideas/experiences with late model Chryslers would be much appreciated. It has the Continental-Teves 4-wheel disc brakes with what I assume to be a Bendix ABS system, but I don't know that for sure.

Thanks!

 

[brianl703]

Originally Posted By: Hokiefyd
Is cycling this ABS pump with the scan tool an absolute necessity?


Only if you've replaced the ABS pump or hydraulic module.

Otherwise, you can bleed the brakes as you normally would.

 

[The Critic]

Originally Posted By: brianl703
Originally Posted By: Hokiefyd
Is cycling this ABS pump with the scan tool an absolute necessity?


Only if you've replaced the ABS pump or hydraulic module.

Otherwise, you can bleed the brakes as you normally would.

+1.

Usually that's the case.

The Chrysler ABS system should be supported by most higher-end aftermarket scan tools. I think anyone with a higher-end Snap On scanner (e.g. Verus) or OTC Genisys should be able to perform a proper bleed without any issues.

If you are going to let the dealer do it (I would), I would check and confirm that they are actually going to perform a proper bleed with the scan tool. Some dealers, for these optional BG/MOC brake flushes, may not actually use the scan tool with the flush process since they are not performing a flush after a repair.

 

[eljefino]

Originally Posted By: Hokiefyd

The van has ABS. The procedure in the service manual talks about using the Chrysler scan tool to cycle the ABS pump and get the fluid in that out as well. Is cycling this ABS pump with the scan tool an absolute necessity?


If you're quoting verbatim, it sounds like the system bypasses the ABS nooks & crannies, but, also, the air bubbles bypass those same nooks.

So your change will be 90% effective, like leaving pools of old oil in an engine, and not problematic, eg, undriveable.

You can always drive it afterwards and hit the abs, mixing the fluid in the module, and bleed again afterwards.

I've had GM ABS bleeds go poorly, but the pedal just had an inch of play and could still lock 'em up/ activate the ABS. (Fear not-- got fixed properly.)

So, if your concern is you'll mess the job up, how much is a tow? $135? What are the odds? Better than 50/50 says DIY.

 

[sciphi]

I had to remove the Buick's ABS unit last winter when replacing the brake lines. After bleeding the first time, some good ABS-helped stops on snow and another bleed set things back to normal.

 

[bigmike]

Why not bleed the system and go activate the ABS on a back road or empty parking lot? Then flush it again. This is what I do each time. Do it often enough (every 2 years or so) and no worries.

I'm open for criticism.

 

[TMoto]

Originally Posted By: eljefino
I've had GM ABS bleeds go poorly, but the pedal just had an inch of play and could still lock 'em up/ activate the ABS.

In the past, I've always done the two person brake bleed method.

I want to use a Mityvac to bleed/flush/exchange(?) the brake fluid on a 2000 Buick Century. The brakes are fine and I'm not changing anything so the system won't be open to having any air in the lines, but I keep reading that bleeding on vehicles with ABS can be an issue. Obviously keep the reservoir topped up, but other than connect the tubing to the bleeder screw, pump the Mityvac, and open the screw, what else should I do or be aware of? Same thing for a 1995 Aerostar with ABS?

/threadjack

 

[Kestas]

I agree with bigmike. They say a poor man's way of cycling the ABS unit is to do a conventional brake fluid exchange, then activate the ABS system on the road. It should dilute the old fluid in the ABS system.

 

[Hokiefyd]

Thanks guys. eljefino, your question about asking whether I was quoting verbatim prompted me to re-read the service manual. This is what it says:

"
The base brake's hydraulic system must be bled anytime air enters the hydraulic system. The ABS though, particularly the ICU (HCU), should only need to be bled when the HCU is replaced or removed from the vehicle. The ABS must always be bled anytime it is suspected that the HCU has ingested air. Under most circumstances that require the bleeding of the brakes hydraulic system, only the base brake hydraulic system needs to be bled.
"

So you and others are correct: since the ABS module has not been replaced and failure there is not suspected, I should be able to move forward with a conventional brake system bleed. And even the ABS system bleed is this:

"
4. Bleed the base brake system using the standard pressure or manual bleeding procedure.
5. Using the scan tool, select ANTILOCK BRAKES, followed by MISCELLANEOUS, then BLEED BRAKES. Follow the instructions displayed. When the scan tool displays TEST COMPLETED, disconnect the scan tool and proceed.
6. Bleed the base brake system a second time. Check brake fluid level in the reservoir periodically to prevent emptying, causing air to enter the hydraulic system.
"

All they're doing is what I'd be able to do even if I did a full ABS bleed: bleed the brakes conventionally, cycle the ABS pump, then bleed them again.

For the conventional bleed, I'm supposed to do them in this order:

Left Rear Wheel
Right Front Wheel
Right Rear Wheel
Left Front Wheel

I guess each manufacturer/brake system has their own order.

Thanks again everyone.

 

[HTSS_TR]

Originally Posted By: TMoto

Obviously keep the reservoir topped up, but other than connect the tubing to the bleeder screw, pump the Mityvac, and open the screw, what else should I do or be aware of? Same thing for a 1995 Aerostar with ABS?


That was exactly how I bleed my 3 cars with ABS using the Mityvac. You're good to go for another 2-3 years before bleeding the brake system again.

 

[mechtech2]

You will be OK with a normal bleed. And it will migrate into the ABS eventually.
Activate the ABS intentionally by driving it in conditions that will cause lock up of some wheels.. You can also jack up a corner and rotate a tire with the brakes lightly applied.